Is there really no other way?

[Manok101]

Is spending 2,000$ US really the only way to truly take photographs using a 10" dob of anything other than planets and the moon?

[Superewza]

Is spending 2,000$ US really the only way to truly take photographs using a 10" dob of anything other than planets and the moon?

No. It depends what you want to do and what your skills are. Hell, get real good at manual tracking and you could spend £30 on an SLR, T-Mount and some film

[RikM]

I would think that's about it yes. EQ6 + rings and a dovetail bar + guide scope and rings + guide camera.

[PortableAstronomer]

Come over to Europe man, and spend double the money for the same stuff.

Serously though, I've seen some pretty awesome stuff taken with a 2nd-hand DSLR camera on a home-made table-top wooden equatorial camera wedge. ( that was a bit of mouthful wasn't it)

[ronin]

Will someone get the simple idea that Dobs and astrophotography do not go together.

Lots of posts say "Of course you can get a picture" with a dob, but look at the picture of the week and other astro images. They were not taken with a dobsonian mounted scope.

A dobsonian mount is not the mount for astrophotography. Many would argue that a newtonian is not the ideal scope for astrophotography.

If you are thinking of some sort of drive for the dobsonian mounted scope you have, then will this just make the unit into a motorised Alt/Az mount? If so that will give field rotation.

If you intend to get a large equitorial mount then that is the mount you need. But to take into account a "safety" margin they say get a mount capable of handling twice the scope weight. A 10" newtonian is HEAVY.

[Manok101]

Well my mount does track, and it is also goto, so my thinking was, get a camera and a t mount, and have at it. Or would that not even be worth the money?

[JamesF]

Tracking can work in different ways though. What you really need for astrophotography is for the scope to track around the earth's axis of rotation so that the image stays in the same relative position to the scope.

Tracking by moving alt and az may keep the object centred, but it will still appear to rotate as it moves across the sky.

James

[Digz]

Will someone get the simple idea that Dobs and astrophotography do not go together.

Lots of posts say "Of course you can get a picture" with a dob, but look at the picture of the week and other astro images. They were not taken with a dobsonian mounted scope.

A dobsonian mount is not the mount for astrophotography. Many would argue that a newtonian is not the ideal scope for astrophotography.

If you are thinking of some sort of drive for the dobsonian mounted scope you have, then will this just make the unit into a motorised Alt/Az mount? If so that will give field rotation.

If you intend to get a large equitorial mount then that is the mount you need. But to take into account a "safety" margin they say get a mount capable of handling twice the scope weight. A 10" newtonian is HEAVY.

Maybe a little harsh. It all depends on the expectations of the OP. If they want to aspire to the standard of photos showcased here and those that get chosen for POW then sure a dob wont do it. But for simplistic AP of the moon then a dob will do.

Well my mount does track, and it is also goto, so my thinking was, get a camera and a t mount, and have at it. Or would that not even be worth the money?

A dob will suffer from field rotation - google it to see what that is.

To get around this you could mount your dob on an EQ platform I have no experience with them but I would imagine you will be limited in your exposure lengths.

[brantuk]

If you've got a tracking dob then you can get some nice results on planets/moon with a webcam. I also saw a thread where the OP had mounted his dob on an EQ platform and got one or two good basic shots of M42. So I'd say have a go at it and see what you can do - you've nothing to lose trying it out.

[Moonshane]

I have made an equatorial platform and if you could make it with engineering tolerances (I bet some could but I cannot) then I feel you could (and some do take Equatorial Platforms - Color Photos by Tom Osypowski ) some excellent DSO images. but the costs of such platforms to buy are, you guessed it, about the same price as an EQ6! Equatorial Platforms: Pricing

if I wanted to get into imaging (which I definitely don't) I would buy a small refractor - 70-90mm aperture and then you can probably get away with a much less expensive mount for a while but eventually everyone seems to gravitate toward the larger expensive mounts when they get serious.

[Hypernova]

I am sure there was link on here a few months back to some amazing short exposure DSO pictures taken through a very large 20"+ dob. It might've been somewhere in the FS section but I can't be quite sure.

IIRC that was tracking in alt-az but the short exposures of only a few seconds or minutes meant that it didn't make any noticeable impact on the image.

[Moonshane]

hi Tom!

I think that's what Superewza was suggestion. people used to track manually, turning a thumbscrew or whatever every minute etc and got decent results. BUT if you want the sorts of results that get POW then you are fighting a losing battle with this sort of kit. as good as a 20" dob is (and I'd love one) there are cheaper and easier ways to do AP.

[WayBig]

I can't believe that someone can't write software to remove field rotation from frames in an avi, seems like such an obvious thing to do...

Registaxx - are you listening?

[RikM]

For long exposure AP with a 10" f/5 scope it really has to a monster EQ mount with an autoguider, but that is not the set-up I would want to start out with to learn imaging.

[Hypernova]

Here is the FS thread with the 22" dob:

http://stargazerslounge.com/sale/138147-22-dobsonian-argo-navis-servocat-goto-tracking-drive-system.html

And a further down in thread I found a link to another forum that showed off pics taken with a similar setup, note the really short exposure times!

A few images taken with SDM Dob - IceInSpace

Would be an ideal imaging AND visual setup I think, best of both worlds

[Crunchard]

I second this:

I can't believe that someone can't write software to remove field rotation from frames in an avi, seems like such an obvious thing to do...

Registaxx - are you listening?

[Tim]

Many would argue that a newtonian is not the ideal scope for astrophotography.

I'd like to meet them. I would firstly, with a smile, point out that Hubble is a reflector. As are all the super size scopes around the globe.

And then would ask them to view some of the finest earth bound astro images from amateurs, and ask them to pick their favourites. Penny to a pound that the most staggering photos taken of the night sky have been achieved with a tube with two mirrors.

There will always be some element of compromise, either on weight, focal ratio, portability, aperture, ease of use etc, and I dont think there IS an ideal scope for astrophotography,

(if you hear of an f3, 5kg tube with 20" aperture and 3000mm focal length and completely flat and perfectly colour corected for £500, do let me know:D ) but there are some extremely useful compromises.

Going back to the OP though, what is it you really want to take photos of? Moon & planets, widefield sky, nebulae or galaxies close up?

Cheers

Tim

[anthony]

You can certainly aspire to POW quality of images but not everyone does and certainly no-one begins at that level so let's not be too dismissive. Everyone starts with mediocre at best and I'd like to state that you CAN take respectable pictures with a tracking DOB.

The quality of the tracking will be critical and you cannot really tell this (from an image taking perspective) until you have a camera attached. The focal length will put pressure on this aspect too. A 10" at F5 will give about 1250mm which is demanding. This will mean that your maximum exposures will be limited. If your skies are dark enough you can still get OK data. My first was an ALT AZ 8" scope at F10 (so 2000mm focal length). The tracking for this is the same as the tracking DOB (up/down, left/right) and I would manage a minute just fine which was enough to catch the brighter stuff (ring nebula, dumbell nebula) and I had great fun getting those images.

The field rotation will show itself when it comes to stacking images and so you will have to crop your frames a bit, but if you centre your target well you can still end up with a decent shot.

How much it'll cost you is another matter altogether! It sounds like you already have the 10" DOB.

DSLRs are ubiquitous and so cheap. They also double up as a superb daytime camera! Treading carefully you can get a well looked after one second hand. You need to read a bit, get hold of some of the free stacking programs, download GIMP for free. All this will get you going for minimal expenditure and importantly - give you "time at the wheel". There is no better way to learn what to do AND to find out if you have the time and inclination to take it further (ie much more than $2000 and POW!).

At the start though the ratio of failure to success is about 10:1 so be prepared…...

[Manok101]

I really was just looking for something to do on the nights (there are many here in the south of the US) where I didn't have clear skies to look. I do know that my camera is capable of short exposure, would that be easier to learn first anyway?

[Superewza]

hi Tom!

I think that's what Superewza was suggestion. people used to track manually, turning a thumbscrew or whatever every minute etc and got decent results. BUT if you want the sorts of results that get POW then you are fighting a losing battle with this sort of kit. as good as a 20" dob is (and I'd love one) there are cheaper and easier ways to do AP.

I agree, dobs aren't ideal for this - i'm just saying that the idea that you have to spend thousands on the latest kit to get a decent picture is completely untrue. For years people used workarounds, tricks and simple bits of kit to get great results - there's no reason the same techniques can't still be employed today.

[rabbithutch]

What is the favored scope type and mount of the ap fanaticsfans?

[Merlin66]

Re software correction of field rotation - it can already be done!

Not a major issue for any of the imaging software packages to rotate one frame relative to the other and then stack them.

The problem really comes down to the length of the exposure and star images trailing on the chip. If the exposure is short enough to give reasonably tight images then you'll get reasonable results.

If you want a software package to take the star trail arcs and then incrementally chop them into star sized bites and re-stack them into one small image....that's a tremendous ask!

[Macavity]

Video cameras (Minitron, Watec etc.) give real-time images of DSOs on screen. If you can "see it", you can "snap" it! <G> I find stacking software will cope with objects that move across field, with minimal tracking - Even a static scope. As above, some software will actually de-rotate images. The result may not be "Hubble quality", but, as a record of your endeavours...

[PNB]

How about doing something like this then?

Looks very industrial but then again, that always works for me, now excuse me while I stomp round my garden to Combichrist waiting for the clouds to vanish....

Paul

[Nexus 6]

Interesting thread with some good answers, it looks like its definately possible Manok, its just that maybe most of us think that a dob is more for visual oberving, you get that big aperture for a great price! Of course like all scopes we are always spending more money on moding and improving them so virtually anything is possible. Go for it if you have the hankering and the cash to try it!